The former U.S. Housing secretary thanked staff members and supporters in Orlando, Tampa and Miami after his narrow defeat of Castor in Tuesday's election. Martinez succeeds Democratic Sen. Bob Graham, who is retiring.

Martinez said the nature of the Senate campaign prevented his new constituents from getting to know him as a person, and he promised to reach out to Democrats and others who did not support him.

He clashed with Castor over the war in Iraq and her handling of a professor accused of terrorist activities during a rough-and-tumble campaign.

"I'm a pretty good guy and I want people to get to know that good guy but I also want people to know that no matter who they voted for, that I'm going to be their senator," Martinez said. "That no matter who they supported that Florida gets to have only two senators and I'm one of them and I'm going to represent all Floridians."

Martinez said he would push for reforms of the nation's intelligence service and Social Security, two proposals expected to be addressed in President Bush's second term agenda, while seeking additional funding for the state's highways and the restoration of the Everglades.

"We'll find ways in which we can reach out, issues in which we can bring people together, because I think that's important," he said.

Martinez, who fled Cuba as a 15-year-old as part of the "Pedro Pan" program, will become the first Cuban-American in the Senate, something he noted by thanking Cuban-American supporters for helping him reach a "historic landmark."

He also celebrated news that with the counting of absentee ballots in Miami-Dade, Martinez carried the county by more than 2,700 votes.

The senator-elect drew cheers from the crowd when he said the White House would continue pushing for human rights and supporting dissidents in Cuba. His elevation to the Senate was a dream come true for supporter Amanda Suarez, who expects Martinez to be a strong voice against Fidel Castro.

"This is like slapping Castro in the face -- that a Peter Pan grows up to be a senator," Suarez said.

Issues aside, the day was one for celebration after a yearlong campaign. Martinez was mobbed by supporters in Miami and cheered by volunteers in Orlando.

"What a great job!" Martinez told about a dozen campaign workers in Orlando. "This reminds me of being in high school and your classmates say, 'What are you doing this summer? Where are you going on vacation?' "